In two recent but separate pioneering studies using methods of measuring ancient mountain elevations, both showing “results that are in tight agreement,” that the Andes Mountains have grown several times faster than geologists have always thought (“Mountain Ranges Rise Dramatically Faster Than Expected,” Science Daily, Science News, Janaury 26, 2006; Carmala N. Garzione, et al., “Tectonic Evolution of the Central Andean Plateau and Implications for the Growth of Plateaus,” Earth and Planetary Science Letters, Annual Review, vol.45, Elsevier Journals, 2017, pp529-559).
Sedimentary deposits near Cerdas in the Altiplano plateau of Bolivia,
where rocks contain ancient soils used to decipher the surface temperature and
surface uplift history of the southern Altiplano
As an example, according to Garzione, "People have largely ignored the role of the mantle lithosphere because it is difficult to look 50 to 200 kilometers [31 to 125 miles] into the earth; whereas we can easily see the deformation on the surface." See the last post for details on this issue.
Regarding the past, she adds, "Some geologists have guessed that the mantle lithosphere is removed continuously and evenly during mountain building. Our data argue that the mantle just accumulates down there until some critical moment when it becomes unstable and drops off." This is a considerably important factor, first that geologists had guessed at something in the past, and that her studies show the past thinking was completely erroneous as to how mountains grew upward—not slowly and gradually in extensive time periods, as they believed, but in short “growth spurts” quite suddenly, as she and her team pointed out.
It also might be of interest to note that this theory has been around since the early 1980s (38 years ago), but it did not stand up to the scrutiny of mainstream science, because the techniques necessary to estimate surface elevation have only been recently developed.
The eclogite anchor keeps the crust from rising as it pulls the
lithosphere downward. When the anchor is heavy enough to break free, the
lithosphere rebounds upward, elevating the hill or mountain
On the other point in the critique from a reader, the early size of South America was impacted by the geologic understanding that most of South America was anciently submerged except for the Andean Shelf along the west coast, the three cratons or shields (Brazilian, Guiana, and Rio de la Plata)—generally a large area of exposed crystalline igneous and high-grade metamorphic rocks that form tectonically stable areas of the continental crust that rise high from the stable craton from which they extend.
Early geologic makeup of South America,
showing the Andean Shelf and two major Shields, of which parts were above the
submerged Amazonian Basin, forming the two major seas, two seaways, and the
Amazon Sea extending along the current river pass between the shields
According to Víctor Alberto Ramos, an Argentine geologist who has contributed to the paleogeography and plate tectonics of South America, claims that the Andean Uplift and the Andean orogeny were characterized by extensional tectonics, rifting, the development of back-arc basins and the emplacement of large batholiths—a large mass of intrusive igneous rock larger than 40 square miles, and made mostly of granite, quarta monzonite or diorite .
The earlier land of Chilenia showing the
morphostructural units of the Andes between 28°S and 36°S latitude, the
inferred boundary between exotic Chilenia and Cuyania terranes; showing Lehi’s
landing site of Coquimbo Bay/La Serena west of the Principal Cordillera and the
eventual coast line (gray dotted line)
According ot Adrian Hartley, palaeoaltitude data suggest that a substantial proto-Central Andean mountain range was in place anciently, and that the data support the idea that therefore the Andean rain shadow also existed which reinforced the pre-existing climatic regime rather than changing it. The change to hyperaridity in western South America is attributed to a combination of global climate cooling and enhanced upwelling of the Humboldt current generated by closure of the Central American Seaway and not to the Andean rain shadow (Adrian J. Hartley, “Andean Uplift and climate Change,” Journal of the Geological Society, Lyell Collection, vo.160, 2003, pp7-10).
All of this, and what is to follow, is meant to show those who have difficulty in getting their minds around ideas such as this that are not in the mainstream of the public conscience (think of the difficulty Joseph Smith and the early Saints had in convincing people of ideas so different than that of all other religions of the time). The point is that South America, like all other lands on this earth do not date back much before 13,000 years according to the Biblical account, and even was dated as such with the initial test of Libby’s C-14 time clock before he changed the basis, was until the crucifixion of Christ as large island running along the Andean Shelf on the west coast of South America, a long, narrow island, in which Lehi landed in the far south and Nephi traveled some distance northward to settle and build his temple and where the Nephites populated for some four hundred years before Mosiah moved farther northward.
However, there is more to understand about the geologic formation of South America, and the Andean Uplift.
(See the next post, “How Could the Continent of South America Have Been an Island During Nephite Times? – Part III, for more on how South America was formed, why it was an island along with a handful of mastiffs and shields, and when and how this changed)
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